From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=BAYES_00,INVALID_DATE autolearn=no autolearn_force=no version=3.4.4 Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!MBUNIX.MITRE.ORG!emery From: emery@MBUNIX.MITRE.ORG (Emery) Newsgroups: comp.lang.ada Subject: O.S. support for lightweight processes Message-ID: <8904041419.AA00580@mbunix.mitre.org> Date: 4 Apr 89 14:19:11 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet List-Id: Bob Hathaway (rjh@purdue.edu) writes: >I haven't looked at the POSIX standard yet but I'm hoping support >for lightweight processes and distributed programming is provided. The existing POSIX standard (P1003.1) does not include either lightweight processes or distributed programming. Nor will it any time soon. This is because the goal of the effort is to standardize existing practice. There is no industry consensus on lightweight processes, the same way there is for other things, such as fork, signals, etc, in Unix. (Note that the POSIX signal model is different from both System V and 4.2 BSD, but not radically so. The differences are in implementation.) The POSIX Real-Time group (P1003.4) has been looking at threads, and MAY include a threads/lightweight process interface in its document. Although not a direct issue for the Ada binding, those of us working on the Ada binding would very much like to see a threads interface that can be used to implement Ada tasks. Besides making the Ada RTS implementor's life easier, hopefully the threads interface would provide for single-level scheduling of all threads (both POSIX/C threads and Ada tasks) across the entire system. I agree that current state-of-the-practice operating systems often get in the way of Ada, but don't look at a Standards activity to fix this problem until the state-of-the-practice is there. Dave Emery emery@mitre.org POSIX Ada Binding (P1003.5) Technical Co-Editor p.s. If you believe this is a "good thing", then consider joining the POSIX effort, either the working group or the balloting group.